Tire

Abstract

The end of the folded-back ply in the tread width direction of the tire ( 1 ) extends beyond the tire maximum width, and the height of the bead filler is 30% or less than the tire sectional height. The maximum thickness of the reinforcing rubber layer is less than the maximum thickness of the bead filler. The tread width is greater than or equal to 81% of the tire maximum width. The radius of curvature of the carcass layer on the extension line passing through the tire maximum width position and extending in the tread width direction is 30 mm or greater.

1 . A tire comprising:
 a tread portion in contact with a road surface;   a pair of bead portions each including a bead core and a bead filler;   sidewall portions extending between the bead portions and the tread portion;   a carcass layer folded back around the bead cores and extending in a toroidal shape between the bead portions;   a belt layer arranged outwardly of the carcass layer in a tire radial direction, the belt layer reinforcing the tread portion; and   reinforcing layers arranged adjacent to the carcass layer on a tread widthwise outer or inner side of the carcass layer, the reinforcing layer reinforcing the sidewall portion,   the carcass layer including a body ply portion extending from the tread portion to the bead cores and folded-back ply portions each folded back around the corresponding bead core,   wherein an end portion of each folded-back ply portion extends beyond a tire maximum width height,   a height of the bead filler is 30% or less of a tire cross-sectional height,   a tire radial inner end portion of each of the reinforcing layers is positioned inwardly, in the tire radial direction, of a tire radial outer end portion of the bead filler,   in a cross section taken along the tread width direction of the tire and taken orthogonally to a tire circumferential direction, a maximum thickness of each of the reinforcing layers is smaller than a maximum thickness of the bead filler,   a tread width, a length of the tread portion in the tread width direction, is 81% or more of a tire maximum width, and   in the cross section taken along the tread width direction of the tire and taken orthogonally to the tire circumferential direction, a radius of curvature of the carcass layer on an extended line extending in the tread width direction through a tire maximum width position is 30 mm or more.   
     
     
         2 . The tire according to  claim 1 , wherein the tread width is 95% or less of the tire maximum width. 
     
     
         3 . The tire according to  claim 1 , wherein
 the carcass layer includes one layer and formed of a plurality of cords inclined against the tread width direction, and   an inclination angle of the cords and the tread width direction is 20 degrees or less.   
     
     
         4 . The tire according to  claim 1 , wherein a length in the tire radial direction between the tire radial inner end portion of each of the reinforcing layers and the tire radial outer end portion of the corresponding bead filler is 10 mm or less. 
     
     
         5 . The tire according to  claim 1 , wherein in the cross section taken along the tread width direction of the tire and taken orthogonally to the tire circumferential direction, the radius of curvature of the carcass layer on the extended line extending in the tread width direction through the tire maximum width position is 60 mm or less. 
     
     
         6 . The tire according to  claim 1 , wherein a height of the bead filler is 25% or less of the tire cross-sectional height. 
     
     
         7 . The tire according to  claim 1 , wherein an end portion of each of the folded-back plies extends to a tire radial inner side of the belt layer and arranged inwardly, in the tread width direction, of a tread widthwise end portion of the belt layer. 
     
     
         8 . The tire according to  claim 1 , wherein a length of each of the reinforcing layers in the tire radial direction is less than 40% of the tire cross-sectional height. 
     
     
         9 . The tire according to  claim 1 , wherein in the cross section taken along the tread width direction of the tire and taken orthogonally to the tire circumferential direction, the radius of curvature of the carcass layer on the extended line extending in the tread width direction through the tire maximum width position is 50 mm or less.